Purpose: The purpose of this study is to describe the workplace culture and factors associated with it from the viewpoint of the personnel providing care to patients with dual diagnosis. Design/methodology/approach: Data were collected from six organizations using an electronic survey in 2019. The respondents (n = 75) worked in addiction psychiatry in specialized health care and provided care to patients. The data were statistically analyzed. Findings: Workplace culture was evaluated as positive. Stress was experienced occasionally (Md = 2.58, Q1 = 1.96, Q3 = 3.03), job satisfaction levels were moderate (Md = 4.83, Q1 = 4.28, Q3 = 5.44) and the practice environment was evaluated as neutral (Md = 4.46, Q1 = 4.00, Q3 = 5.04). Gender, age in years, employment relationship, work time, staffing, number of patients and the participants' experience in health care and experience in their current workplace had statistically significant associations with workplace culture. Originality/value: In Finland, there have been attempts to reform service structures that also influence mental health and substance addiction services. Workplace culture is one approach to promote service development. Yet, there has been no research on workplace culture in the context of the care of patients with dual diagnosis. The results of this study bring knowledge about how health-care personnel perceives stress, job satisfaction and their practice environment in addiction psychiatry, which can be used to further develop services and workplace culture. [ABSTRACT FROM AUTHOR]